The potential protective effect of ICRF-187, a bisdiketopiperazine compound (1,2-bis(3,5-dioxopiperazin-1-yl(propane) against the chronic cardiomyopathy induced by daunorubicin and doxorubicin, was evaluated in rabbits, beagle dogs and miniature pigs. The results obtained show that ICRF-187 reduces markedly the severity of this cardiomyopathy without producing undesirable side effects.